Method and apparatus for spinning and texturing a multifilament composite yarn

ABSTRACT

A method and an apparatus for spinning and texturing a multifilament composite yarn. The composite yarn is formed from a plurality of yarn components, which are spun, cooled, drawn, and textured in parallel relationship. To obtain physical properties that are adapted to the quality characteristics of the yarn components, the invention provides for drawing at least one of the yarn components separately and independently of the other yarn components before texturing. To this end, a plurality to separate feed roll systems are provided, with at least one of the feed roll systems being associated to the one of the yarn components, and with the one yarn component being drawn by the feed roll system separately and independently of the other yarn components.

CROSS REFERENCE TO RELATED APPLICATION

The present application is a continuation of international applicationPCT/EP2003/008810, filed 8 Aug. 2003, and which designates the U.S. Thedisclosure of the referenced application is incorporated herein byreference.

BACKGROUND OF THE INVENTION

The invention relates to a method for spinning and texturing amultifilament composite yarn as well as an apparatus for carrying outthe method.

A generic method as well as a generic apparatus for spinning andtexturing a multifilament composite yarn are disclosed in EP 0 784 109A2 and corresponding U.S. Pat. No. 6,119,320.

For producing a textured composite yarn by the method disclosed in thereferenced patents, a plurality of yarn components are initially spunfrom a thermoplastic melt by a spinning means, then cooled, andseparately pretreated in parallel side-by-side relationship. The yarncomponents are jointly withdrawn from the spinning means by a withdrawalsystem, and drawn before undergoing texturing. For texturing thecomponent yarns, the latter are textured jointly or parallel inside-by-side relationship and subsequently combined to form a compositeyarn.

The known method is directed to changing the appearance of the compositeyarn by a separate compacting step, essentially by separately entanglingor separately texturing the differently dyed yarn components. However,such visual properties represent only a part of the properties of theyarn which are desired for further processing. For the use andapplication of fabrics produced from such composite yarns, such as, forexample, carpets, the physical properties, such as strength andelongation take priority over visual properties. In this respect, theknown method and the known apparatus play only a subordinate role in theproduction of qualitatively superior composite yarns.

Likewise, the method disclosed in EP 0 861 931 A2 and U.S. Pat. No.6,442,923, attempts to influence in particular the visual properties ofa composite yarn formed from yarn components by separate and individualtreatment of yarn components. In this process, freshly spun and drawnyarn components, or drawn individual yarns that are unwound from apackage, are separately treated in different ways by entangling,texturing, or false twisting, and combined to a composite yarn.

It is an object of the invention to provide a generic method forspinning and texturing a multifilament composite yarn as well as ageneric apparatus for carrying out the method, which permit producingqualitatively superior textured composite yarns with optimized physicaland visual properties.

A further object of the invention is to provide a method and anapparatus, which permit treating parallel spun yarn components or yarnswith greatest flexibility until they are wound.

SUMMARY OF THE INVENTION

The invention is based on the knowledge that after spinning, yarncomponents that are parallel spun from a basic polymer, may have anindividual molecular structure as a result of adding differentadditives, for example, different dyes. When advancing and drawing theyarn components jointly, this individual molecular structure will leadto different physical properties, in particular different strengths.This is where the invention comes into play, in that at least one of theyarn components is drawn separately and independently of the other yarncomponents before being textured. It was thus found that in theproduction of a composite yarn from an individual polypropylene yarnthat had been dyed blue, and a second undyed polypropylene yarn,different draw ratios lead to respectively maximum strengths withsimultaneously the least residual elongations in the yarn components.Thus, the blue dyed yarn component required a draw ratio of 1:2.5, andthe undyed yarn component required drawing at the ratio of 1:3.5. Withthat, the invention permits the purposeful influencing of the physicalproperties of the yarn components in a manner that it is possible toproduce a composite yarn of maximum strength, while havingsimultaneously a minimal residual elongation.

To obtain during the spinning of the yarn components a drawing that isadapted to the characteristics of the yarn component, an advantageousfurther development proposes to withdraw a yarn component duringspinning separately and independently of the other yarn components at awithdrawal speed that differs from the withdrawal speeds of the otheryarn components.

In a preferred embodiment of the method, wherein to each yarn componenta plurality of separate feed roll systems are associated, which withdrawthe yarn components during the spinning separately and advance themseparately for drawing, it is possible to adjust on each of the yarncomponents the maximum strength with the least residual elongation. Withthat a very uniform and qualitatively superior crimp can be realized ineach of the yarn components after texturing.

To improve the visual properties of the composite yarn, it is possibleand advantageous to entangle the yarn components separately beforedrawing by means of a pressurized fluid.

To obtain an as uniform and superior crimp as possible when texturingthe yarn components after spinning, it is preferred to apply the stufferbox principle in the texturing step. To this end, it is possible tocompress the yarn components after drawing either separately or jointlyto form a yarn plug in a stuffer box chamber. Because of the greatstrength of the yarn components, it is possible to reach very great yarnplug densities, which result in an intensive formation of loops andcurls in the individual filaments of the yarn components and, thus, inan intensive crimp.

Before winding the composite yarn, the latter is formed preferably byentangling or texturing the yarn components. The choice in which way theyarn components are combined to the composite yarn is essentiallydetermined by the desired visual properties of the composite yarn. Forexample, to obtain in the case of a multicolor yarn a distinct,accentuated mixed color, it is preferred to produce the composite yarnafter separately texturing the yarn components by entangling.

To carry out the method, a withdrawal system is provided which is formedby a plurality of feed roll systems, with at least one feed roll systembeing associated to one of the yarn components. The yarn component beingdrawn by the one feed roll system is thus drawn separately andindependently of the other yarn components.

The feed roll system associated to the one yarn component is made forseparate operation and control, so that an individual adjustment ispossible for withdrawing and drawing the yarn component.

The highest flexibility for carrying out the method is ensured by anadvantageous further development of the apparatus, wherein the feed rollsystems are associated to the yarn components such that each of the yarncomponents is withdrawn and drawn independently of adjacent yarncomponents.

In this arrangement, the feed roll systems can be operated or controlledindividually or in groups.

For texturing the yarn components, the texturing means is formedpreferably by a feed nozzle and a stuffer box chamber cooperating withthe feed nozzle. The feed nozzle is preferably operated with a hotconveying medium, so that the yarn components or the formed yarn plugundergo a thermal treatment at the same time. For cooling the yarn plugsemerging from the stuffer box chamber, a cooling unit is provided whichcools the yarn plugs by means of a cooling medium.

The method and the apparatus of the invention are also suited forproducing a composite yarn, whose yarn components are spun fromdifferent polymers. In this connection, it is possible to spin basicallyall known polymer materials, such as, for example, polyamide, polyester,or polypropylene.

In the case that the composite yarn is produced from feed yarn packages,it is advantageous to apply the method of the invention wherein theyarns are parallel spun from a polymer melt, cooled, and drawn beforebeing textured, separately and independently of one another by aplurality of feed roll systems that are associated to the yarns. Afterdrawing, the yarns are separately textured and each wound to a package.It is also preferred to use the method for the production of identicalyarns. The individual treatment of the yarn components until they arewound is however used preferably in the case of different quality of theyarns.

BRIEF DESCRIPTION OF THE DRAWINGS

In the following, the methods of the invention are described in greaterdetail by means of several embodiments of the apparatus according to theinvention with reference to the attached Figures, in which:

FIG. 1 is a schematic view of a first embodiment of the apparatusaccording to the invention;

FIG. 2 is a schematic view of a second embodiment of the apparatusaccording to the invention;

FIGS. 3 and 4 are schematic views of some embodiments of a withdrawalmeans of the apparatus according to the invention; and

FIG. 5 is a schematic view of a further embodiment of an apparatus forcarrying out the method of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The apparatus as shown in FIG. 1 comprises a spinning means 1 thatconnects to one or more melt producers (not shown). The spinning means 1includes a heated spin beam 2, which mounts in side-by-side relationshipa plurality of spinnerets 3.1-3.3. The spinnerets 3.1-3.3 each compriseon their underside a plurality of spin holes, through which a polymermelt which is supplied to each of the spinnerets 3.1-3.3 flows. The meltis thus extruded under pressure to form a plurality of groups ofindividual filaments.

Downstream of the spin beam 2, a cooling shaft 4 is provided, throughwhich the groups of extruded filaments advance, so that the filamentsemerging at approximately the melt point are cooled. To this end, thecooling shaft 4 could connect, for example, to an air flow system, whichblows cooling air substantially transversely toward the filaments. Aftercooling the filaments, the filament groups associated to respectivespinnerets 3.1-3.3 are combined to form a yarn component 6.1-6.3 by yarnguides 5.1-5.3 at the outlet of the cooling shaft 4.

Downstream of the spinning means 1 is a withdrawal means 10 forwithdrawing the yarn components 6.1-6.3 from the spinnerets 3.1-3.3. Thewithdrawal means 10 is formed by a plurality of feed roll systems14.1-14.6 which are associated to each of the yarn components 6.1-6.3.Thus, the yarn component 6.1 is withdrawn from the spinning means 1 byfeed roll system 14.1, the yarn component 6.2 by feed roll system 14.2,and the yarn component 6.3 by feed roll system 14.3. The feed rollsystems 14.1-14.6 are each formed by a driven godet and an associatedcompanion roll, which are looped by the respective yarn componentseveral times. In particular, the drives of the feed roll systems14.1-14.3 are controllable independently of one another, so that it ispossible to adjust a withdrawal speed that is adapted to the particularyarn component.

To be able to draw the yarn components 6.1-6.3 in full, the feed rollsystems 14.1-14.3 are each followed by an additional feed roll system14.4-14.6. Thus, the yarn component 6.1 advances through feed rollsystems 14.1 and 14.4, the yarn component 6.2 through feed roll systems14.2 and 14.5, and the yarn component 6.3 through feed roll systems 14.3and 14.6. The feed roll systems 14.4-14.6 are operated preferablylikewise independently of one another by separate drive units. In thecase that all yarn components 6.1-6.3 are removed by the withdrawalmeans 10 at the same yarn speed, the feed roll systems 14.4-14.6 can beactivated preferably via a common control unit. In this case, it wouldalso be possible to combine the individual drives of the feed rollsystems 14.4-14.6 to a group drive. In the cases, in which thewithdrawal means 10 removes the yarn components 6.1-6.3 at differentyarn speeds, for example, to realize visual effects on a composite yarn,the drives of the feed roll systems 14.4-14.6 are separately operatedand controlled.

To pretreat the yarn components 6.1-6.3, a pretreatment means 8 isprovided between the spinning means 1 and the withdrawal means 10. Thepretreatment means 8 is formed by yarn lubrication units 7.1-7.3associated to each of the yarn components 6.1-6.3 and subsequententanglement nozzles 9.1-9.3. In this arrangement, a lubricant isapplied to each of the yarn components 6.1-6.3 independently of theothers. Subsequently, the filaments of the yarn components undergo anentanglement, each in its associated entanglement nozzle 9.1-9.3. Withthat a yarn cohesion is essentially produced for the further treatmentof the yarn components 6.1-6.3.

The further treatment of the yarn components 6.1-6.3 occurs downstreamof the withdrawal means 10 in a texturing means 11 and an aftertreatmentmeans 12. In the embodiment of FIG. 1, the texturing means 11 is formedby a feed nozzle 15 and a stuffer box chamber 16 cooperating therewith.The feed nozzle 15 connects to a source of pressure, which supplies aconveying medium to the feed nozzle 15. The conveying medium draws theyarn components 6.1-6.3 into the feed nozzle 15 and subsequentlycompresses them to a yarn plug in the stuffer box chamber 16. Thiscauses the yarn components 6.1-6.3 to intermingle in part. Subsequently,the yarn plug which is preferably produced by a heated conveying medium,advances to a cooling unit 17, and undergoes cooling. To treat thetextured yarn components 6.1-6.3, the aftertreatment means 12 downstreamof the texturing means 11 comprises a first withdrawal godet 18.1downstream of the cooling unit 17. Downstream of the withdrawal godet18.1 is a combining means 19 which finally intermingles the yarncomponents 6.1-6.3 to form a composite yarn 21. In the presentembodiment, the combining means 19 is likewise formed by an entanglementnozzle. An additional withdrawal godet 18.2 removes the composite yarn21 from the combining means 19 and advances it to a takeup means 13. Thetakeup means 13 winds the composite yarn 21 to a package 20.

In the embodiment of the device according to the invention asillustrated in FIG. 1, the spinnerets 3.1-3.3 are used to spin threeyarn components 6.1-6.3 in a parallel side-by-side relationship. Theyarn components 6.1-6.3 may be produced from different polymercompositions. For example, each of the yarn components 6.1-6.3 couldinclude a different dye, an admixture of a different additive, ordifferent basic polymers. To obtain as much as possible uniform physicalproperties despite the different material qualities of the yarncomponents 6.1-6.3, the yarn components 6.1-6.3 are withdrawn from thespinnerets 3.1-3.3 by their respective feed roll systems 14.1-14.3 at anindividually adjusted withdrawal speed. They are subsequently drawn bythe feed rolls systems 14.4-14.6 downstream thereof. With that, adrawing can occur that is adapted to each of the yarn components 6.1-6.3for the purposes of purposefully and separately influencing andadjusting desired physical properties, such as strength and elongation.

After having been drawn, the yarn components 6.1-6.3 are jointlytextured and combined to the composite yarn 21. The composite yarn 21that is produced by the method of the invention distinguishes itself bygreat uniformity in its physical properties. It is thus possible andadvantageous to produce high-strength yarns. Depending on desire andrequirements for visual properties, it is possible to operate with aplurality of treatment steps.

FIG. 2 illustrates a further embodiment of a device according to theinvention for carrying out the method of the invention. The embodimentis essentially identical to the foregoing embodiment, so that theforegoing description is herewith incorporated by reference and thatonly differences are described. Components having identical functionshave been provided with identical numerals.

In the embodiment of FIG. 2, the spinning means 1, the pretreatmentmeans 8, the withdrawal means 10, the aftertreatment means 12, and thetakeup means 13 are constructed identical to the foregoing embodiment.

For texturing the yarn components 6.1-6.3, the texturing means 11 isformed by separate feed nozzles with associated stuffer box chambers.Thus, the texturing means 11 is composed of feed nozzles 15.1-15.3 andtheir associated stuffer box chambers 16.1-16.3. Downstream of thestuffer box chambers 16.1-16.3 are cooling units 17.1-17.3. The feednozzles 15.1-15.3 and the stuffer box chambers 16.1-16.3 can be arrangedin separate housings or in a common housing. Likewise, the cooling units17.1-17.3 can be replaced with one structural unit, along which threeparallel yarn plugs advance. Essential in the embodiment shown in FIG. 2is that after being individually drawn, the yarn components 6.1-6.3 areseparately textured. Besides the optimized physical properties, it isthus possible to produce in the composite yarn 21 in particular alsospecial visual properties. After separately texturing the yarncomponents 16.1-16.3, same are jointly removed from the respective yarnplugs by withdrawal godet 18.1 and advanced to the combining means 19for forming the composite yarn 21.

The withdrawal means of the embodiments shown in FIGS. 1 and 2 areexemplary in their arrangement and construction. Thus, it is possible tocombine the withdrawal means in the illustrated embodiments in any wayto realize a draw ratio that is adapted to the yarn components.

FIG. 3 illustrates a further embodiment of a withdrawal means, as couldbe used, for example, in the device of FIG. 1 or 2. In the case of thisembodiment, the feed roll systems 14.1 and 14.3 are associated to theyarn component 6.1, whereas the yarn components 6.2 and 6.3 advancetogether over the feed roll systems 14.2 and 14.4. It is thus possibleto advance and draw the yarn component 6.1 independently of the yarncomponents 6.2 and 6.3. The yarn components 6.2 and 6.3 are jointlyadvanced and drawn by the feed roll systems 14.2 and 14.4. Likewise, inthis embodiment, the feed roll systems 14.1-14.4 are formed by a drivengodet and an associated guide roll. Associated to each of the drivengodets is an individual drive unit which is independently controllable.

FIG. 4 illustrates a further embodiment of a withdrawal means, as couldbe used, for example, in the devices of FIGS. 1 and 2. In thisembodiment, the feed roll system 14.1 withdraws the yarn component 6.1.The yarn components 6.2 and 6.3 are jointly withdrawn by the feed rollsystem 14.2. The further drawing of the yarn components 6.1-6.3 thenproceeds jointly by feed roll system 14.3. The feed roll systems14.1-14.3 are operated at different circumferential speeds, so that theyarn component 6.1 undergoes a different drawing than the other yarncomponents 6.2 and 6.3. The yarn components 6.1-6.3 are then jointlyadvanced by the feed roll system 14.3 to the texturing unit downstreamthereof.

FIG. 5 illustrates an embodiment of an apparatus, which permits carryingout the method of the invention for producing parallel spun yarns. Otherthan in the foregoing embodiments, after spinning, each of the yarncomponents 6.1 and 6.2 is treated, textured, aftertreated, and woundindependently of the other. To this end, the takeup means 13 comprises aplurality of winding positions 22.1 and 22.2. In each of the windingpositions 22.1 and 22.2, a yarn component 6.1 and 6.2 is each wound to apackage 20.1 and 20.2. Between the spinning means 1 and the takeup means13, a pretreatment means 8, withdrawal means 10, texturing means 11, andaftertreatment means 12 are arranged. In this arrangement, each meanspreferably comprises for each yarn component 6.1 and 6.2 identicaltreatment means and units. Essential is that each of the treatment meansand units arranged in the path of the yarn components 6.1-6.2 isindependently and separately controllable to enable an individualtreatment of the yarn components 6.1 and 6.2. After the individualtreatment steps, the yarn components 6.1 and 6.2 form yarns 21.1 and21.2 which are wound at an identical winding speed to the packages 20.1and 20.2.

Associated to each of the yarn components are, a lubrication means 7.1,7.2, an entanglement nozzle 9.1, 9.2, a first feed roll system 14.1,14.3, a second feed roll system 14.2, 14.4, a feed nozzle 15.1, 15.2with a stuffer box chamber 16.1, 16.2, a cooling unit 17.1, 17.2, afirst withdrawal godet 18.1, 18.3, an entanglement nozzle 9.1, 9.2, aswell as a second withdrawal godet 18.2, 18.4 one following the other inthe path of the advancing yarn. An arrangement of this type isparticularly suited for producing different yarns 21.1, 21.2 within aspinning apparatus. When spinning the yarns, it is then possible to takeinto account in particular individually adjusted withdrawal speeds anddraw ratios.

The described embodiments for carrying out the method of the inventionare exemplary in their arrangement and selection of the treatment units.Additional pretreatment or aftertreatment steps and means may beintroduced to be able to perform, for example, additional treatments onthe yarn components before or after texturing them, or to carry outadditional treatments on the composite yarn. Likewise, the type and theconstruction of the texturing means is exemplary. To adjust definedcrimps, the yarn components may also be textured, each with differentparameters. In the case of separate texturing, it is also possible toapply different texturing methods. The separate adjustment of the drawparameters on the yarn components provides a high flexibility in theproduction of textured composite yarns.

Likewise, the configuration of the feed roll system in the illustratedembodiments is exemplary. It would thus be possible to construct all orpart of the feed roll systems with respectively two driven godets. Bothgodets of a feed roll system could be operated at the same or differentcircumferential speeds. In addition, one or both godets of a feed rollsystem could include heating means to be able to perform a thermaltreatment on the yarns.

1. A method of spinning and texturing a multifilament composite yarnwhich is composed of a plurality of individual yarn components,comprising the steps of melt spinning a plurality of individualmultifilament yarn components so as to advance parallel to each other,while cooling and drawing the individual yarn components, and includingdrawing at least one of the individual yarn components separately andindependently from the other individual yarn components, then texturingthe individual yarn components separately or jointly, gathering togetherthe individual yarn components to form a composite yarn, and winding thecomposite yarn into a package.
 2. The method of claim 1, wherein themelt spinning step includes withdrawing the yarn components fromrespective spinnerets, and wherein the step of separately andindependently drawing at least one of the yarn components includeswithdrawing the at least one of the yarn components at a withdrawalspeed which is different from the withdrawal speeds of the otherindividual yarn components.
 3. The method of claim 1 wherein a pluralityof feed roll systems are associated with each of the individual yarncomponents by which the individual yarn components are separatelyadvanced for the purpose of being drawn.
 4. The method of claim 1,wherein before being drawn, the individual yarn components areseparately entangled by means of a pressurized fluid.
 5. The method ofclaim 1, wherein after having been drawn, the individual yarn componentsare each separately compressed to a yarn plug in separate stuffer boxchambers for the purpose of being textured.
 6. The method of claim 1,wherein after having been drawn, the individual yarn components arejointly compressed to a yarn plug in a stuffer box chamber for thepurpose of being textured.
 7. The method of claim 1, wherein thecomposite yarn is formed by entangling or by texturing the individualyarn components.
 8. An apparatus for spinning and texturing amultifilament component yarn, comprising a melt spinning device for meltspinning a plurality of individual multifilament yarn components, awithdrawal system for withdrawing and drawing the individual yarncomponents, a texturing device for texturing the individual yarncomponents, a combining device for gathering the individual yarncomponents to form a composite yarn, a take-up device for winding thecomposite yarn into a package, wherein the withdrawal system comprises aplurality of separate feed roll systems, with at least one of the feedroll systems being associated to one of the yarn components so that theone yarn component is drawn separately and independently of the otherindividual yarn components.
 9. The apparatus of claim 8, wherein the atleast one feed roll system is constructed for separate operation andcontrol.
 10. The apparatus of claim 8 wherein the feed roll systems areassociated to the individual yarn components such that each of theindividual yarn components is withdrawn and drawn independently ofadjacent individual yarn components.
 11. The apparatus of claim 10,wherein the feed roll systems are constructed to be operated andcontrolled individually or in groups.
 12. The apparatus of claim 8wherein the texturing device comprises a feed nozzle and a stuffer boxchamber cooperating with the feed nozzle.
 13. The apparatus of claim 12,wherein downstream of the stuffer box chamber a cooling unit extends, bywhich a yarn plug emerging from the stuffer box chamber can be cooled.14. The apparatus of claim 8, wherein the combining device is formed byan entanglement unit, in which the individual yarn components areentangled with one another by means of a pressurized fluid.
 15. A methodfor spinning and texturing a plurality of yarns, comprising the steps ofmelt spinning parallel yarns from a polymer melt and then cooling anddrawing the yarns, and wherein the yarns are then separately texturedand wound to a package, and wherein during the drawing step the yarnsare drawn separately and independently of one another by a plurality offeed roll systems associated with the yarns, with the feed roll systemsbeing constructed to be operated and controlled individually or ingroups.